Answer:
x²(9x– 11)(9x + 11)
Step-by-step explanation:
81x⁴ – 121x²
The expression can be factorised as follow:
81x⁴ – 121x²
x² is common to both term. Thus:
81x⁴ – 121x² = x²(81x² – 121)
Recall:
81 = 9²
121 = 11²
Therefore,
x²(81x² – 121) = x²(9²x² – 11²)
= x²[(9x)² – 11²]
Difference of two squares
x²(9x– 11)(9x + 11)
Therefore,
81x⁴ – 121x² = x²(9x– 11)(9x + 11)
Replace all the x's in the equation with -5. f(5)=(5)2-5+2. > 10-5+2 > 5+2= 7
The Answer is 7
7.030124314 they all just have to be less then 5
Answer:
The minimum cost per unit is obtained for an order of 8 units.
Step-by-step explanation:
Since the total cost is modeled by;
C(x)=5x²+320
Then;
1 unit costs; C(x)=5(1)²+320 = 325
cost per unit 325/1 = 325
8 units costs; C(x)=5(8)²+320 = 640
cost per unit = 640/8 = 80
80 units costs; C(x)=5(80)²+320 = 32320
Cost per unit = 32320/80 = 404
The minimum cost per unit is obtained for an order of 8 units.
